hola se me aparece ReferenceError: $ is not defined saben xq? <code>const API_URL = 'https://swapi.dev/api/' const PEOPLE_URL = 'people/:...

hola se me aparece ReferenceError: $ is not defined saben xq?

const API_URL = 'https://swapi.dev/api/'
const PEOPLE_URL = 'people/:id'
const opts = { crossDomain: true }

function obtainCharacter(id){
  return new Promise((resolve, reject)=>{
    const url = `${API_URL}${PEOPLE_URL.replace(':id', id)}`
    $
    .get(url, opts, function (data){
      resolve(data)
    })
    .fail(() => reject(id))
    })
  }


function onError(id){
  console.log(`Sucedió un error al obtener el character ${id}`)
}

  obtainCharacter(1)
  .then(function (character){
    console.log(`El personaje 1 es ${character.name}`)
  })
  .catch(onError)```